/Engine/Source/Editor/Experimental/EditorInteractiveToolsFramework/Public/ToolContexts/ToolStackContext.h
Registers and maps the provided UI command to actions that start / stop multiple tools within a tool stack Later on this UI command can be referenced to add the tool stack to a toolbar.
virtual void RegisterToolStack ( [TSharedPtr](API\Runtime\Core\Templates\TSharedPtr)< [FUICommandInfo](API\Runtime\Slate\Framework\Commands\FUICommandInfo) > UICommand, const [FString](API\Runtime\Core\Containers\FString) & ToolStackIdentifier, EToolsContextScope ToolScope )